x1,y1,x2,y2=map(float,input().split())
d=((x1-x2)**2 + (y1-y2)**2)**(1/2)
print(d) x1,y1,x2,y2=map(float,input().split()) x1 map(float,input().split()) map float input().split() ().split () input split y1 x2 y2 d=((x1-x2)**2 + (y1-y2)**2)**(1/2) d ((x1-x2)**2 + (y1-y2)**2)**(1/2) (x1-x2)**2 + (y1-y2)**2 (x1-x2)**2 x1-x2 x1 x2 2 (y1-y2)**2 y1-y2 y1 y2 2 1/2 1 2 print(d) print d x1,y1,x2,y2=map(float,input().split()) map(float,input().split()) x1 y1,x2,y2=map(float,input().split()) map(float,input().split()) y1 x2,y2=map(float,input().split()) map(float,input().split()) x2 y2=map(float,input().split()) map(float,input().split()) y2 d=((x1-x2)**2 + (y1-y2)**2)**(1/2) ((x1-x2)**2 + (y1-y2)**2)**(1/2) d
x1,y1,x2,y2=map(float,input().split())
d=((x1-x2)**2 + (y1-y2)**2)**(1/2)
print(d)
